<div class="colorpicker">
  <canvas #myCanvas></canvas>
  <div class="knob" #knob></div>
  <div class="pickerbox" #pickerbox (tap)="tapEvent($event)" (panstart)="panstartEvent($event)"
    (panmove)="panmoveEvent($event)" (panend)="panendEvent($event)">
  </div>
</div>